Heat transfer fin



March 21, 1961 J. J. GANNON HEAT TRANSFER FIN Filed Feb. 26, 1958 INVENTOR J annflrv United States Patent 2,976,022 HEAT TRANSFER FIN John J. Gannon, Clinton, Mass, assignor to Lancaster Engineering Co., Clinton, Mass, a corporation of Massachusetts Filed Feb. 26, 1958, Ser. No. 717,658

1 Claim. (Cl. 257-262.16)

The present invention relates to heat transfer fins of the character which are suitable for heating andcooling pipes utilized in room heating and room cooling and for other purposes.

A purpose of the invention is to permit mounting heat transfer fins in a stable relationship around existing piping without disassembling the piping.

A further purpose is to provide U-shaped heat transfer fin elements which lock to one another at the base of the U and which have axially extending interlocking tongues and grooves from the arms of the U.

A further purpose is to make a complete fin assembly by two halves located at a particular position along the pipe, each of the halves being of U shape with the Us positioned back to back and at least one of the halves having from the arms of the U axially protruding interlocks to the next pair of fin elements.

Further purposes appear in the specification and in the claim.

In the drawings I have chosen to illustrate one only of the numerous embodiments in which my invention may appear, selecting the form shown from the standpoints of convenience in illustration, satisfactory operation and clear demonstration of the principles involved.

Figure 1 is a fragmentary perspective showinga pair of fin elements cooperating to surround a pipe.

Figure 2 is an exploded perspective showing the fin elements about to be assembled.

Figure 3 is a plan view of an assembly of fin elements showing the pipe in phantom.

Figure 4 is a section of Figure 3 on the line 4-4.

Describing in illustration but not in limitation and referring to the drawings:

In the prior art eflforts have been made to mount fin elements on pre-existing pipe such as heating and cooling piping. Difiiculty has been found in such assemblies due to the fact that the tolerance variation in the outside of a pipe of a given nominal size is consderable, and it is diificult to lock fin combinations in a position which will not change under vibration commonly encountered in piping. It is also difiicult to accomplish the initial assembly of the fins in uniform rotational relationship.

In the improved construction of the present invention, each of the U-shaped fin halves is provided with an axially extending interlock to the next set of fin halves, so that the fin combination cannot change its position rotationally with respect to the fin combinations adjoining on each side.

Considering the construction in detail, each of the fin halves comprises a pair of spaced U bases 20 and 21 and a pair of generally parallel U arms 22 and 23, each of which is cut out between the U bases to provide a semicircular hole 24 which will surround the pipe.

At a position adjoining the edge of the hole, suitably at the position most remote from the U bases, a protru- Patented Mar. 21, 1961 sion 25 extends axially, being provided on one of the arms of the U with an axially extending tongue 26, and on the opposite arm of the U with a cooperating recess 27.

Suitable fastening means are used to connect together the fin halves, the form shown illustrating a lanced projection 28 from each of the bases 20 and a cooperating slot 30 on each of the bases 21, the lanced projections being bent over as shown in Figure 4 to hold the U-shaped fin portions around the pipe 31. It is desirable also to provide cooperating holes '32 which can receive bolts or drive screws in case this method of attachment is preferred to bending over the projections 28.

When the fins are assembled on the pipe, as by bending over the projections 28 or using bolts or drive screws in the openings 32, it will be evident that the protrusions having the tongues 26 all extend in one axial direction from a particular pair of fin elements and the protrusion having the cooperating recesses 27 all extend in the opposite axial direction.

It is thus very easy in building up a fin assembly to add additional fin elements to either end, and to maintain them accurately in rotational registration with those previously used.

It will be evident that the invention guards against the possibility that a careless installer may place adjoining pairs of fins elements so close together that they cannot efiiciently rotate, or may place them unnecessarily far apart. The combination of the tongues and recesses assures that an optimum and uniform placement can be obtained without special care by the installer.

In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claim.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

A heat transfer fin construction comprising a pair of cooperating U-shaped fin elements each of which has two spaced bases of the U which cooperate with the bases of the U of an opposing fin element of said pair and each of which has arms of the U which comprise heat dissipating fins, there being a semicircular opening through the arms of the U between the spaced bases of the U, a first extension extending perpendicularly endwise from one of the arms of the U and having a cross section corresponding to the curvature of the semicircular opening, a tongue integral with and extending from said first extension, a second extension extending perpendicularly enwise from the other arm of the U in a direction opposite that of the said first extension, and said second extension having a cross section corresponding to the curvature of the semicircular opening, a notch in said second extension, said tongue on said first extension being adapted to cooperate with a notch on a second extension of an adjoining fin, and means acting across between bases of the us of said pair of fin elements uniting the fin elements together.

References Cited in the file of this patent UNITED STATES PATENTS 2,557,760 Powell et a1. June 19, 1951 2,709,074 Gannon May 24, 1955 FOREIGN PATENTS 322,471 France June 25, 1902 667,479 France June 17, 1929 764,169 France Feb. 26, 1934 

